She knows what a tidy woman mother is, and how clean she keeps the cottage.

她知道妈妈爱干净，总把小屋打扫得干干净净的。

youdao

How clean the roads are!

道路多么干净啊！

youdao

How clean and tidy the room is!

多么干净整洁的房间啊！

youdao

"There are different ways of evaluating how well stormwater practices clean water things like ponds and wetlands and permeable pavement."

VOA: standard.2010.08.04

Within our own rooms, it doesn't really matter how clean they are,

我们自己屋干不干净其实并不重要，

有趣的室友们 - SpeakingMax英语口语达人

And the way it manifests itself, as you know from just how people talk, is you're compulsive, you're clean, you're stingy.

这种人格表现为，强迫，有洁癖和吝啬，这些都可从人们谈话方式看出。

耶鲁公开课 - 心理学导论课程节选

But the best testament to how clean and green Copenhagen really is can be found in the heart of the city.

BBC: Living green in Copenhagen

Many analyses have shown how clean energy legislation will create 1.7 million jobs and opportunities for low-income families, including lower energy bills.

FORBES: Digging Into The Senate Climate Bill

How clean is that?

BBC: Doctors